Alexander wurts



(No Model.)

A. WURTS. LIGHTNING ARRESTBR.

N0. 532,353. 7 Patented Jan. 8, 1895.

WITNESSES:

ATTORNEYS.

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3o plate being removed. Fig.2 is a side eleva- UNITED STATES.

PATENT ()FFICE.

ALEXANDER WURTS, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO THE.

WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, OF SAME PLACE.

LlGHTNlNG-ARRESTERN SPECIFICATION forming part of Letters Patent No. 532,353, dated January 8, 1 895.

Application filed February 28, 1894. Serial No, 501,781- (No model.)

To 06 whom, it may concern.- 7

Be it known that I, ALEXANDER WURTS, a citizen of the United States, residing in Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Lightning-Arresters, (Case No. 58],) of which the following isa specification. v

The object of my invention is to provide an improvement in a form of lightning arrester invented by me and making the subject matter of United States Patent No. 509,784..

Myinvention contemplates the provision of an improved lightning arrester of this class wherein certain dangers to the life of the device itself, due to the great strain to which it is subjected in practice, may be obviated.

I have found in using lightning arr-esters of this class, that a considerable expansive pressure is frequently exerted between the sup-' porting and cover plates of the device, due

probably to the sudden expansion of air which takes place when a discharge occurs between said plates. In order to relieve this pressure and obviate this difficulty, which frequently has resulted in rupture of the plates, I have devised the improvement illustrated in the accompanying drawings, in which- Figure 1 is a plan view of the sparking terminals and their supporting plate, the covertion of the complete device.

In the drawings the supporting plate is shown at 1, and the sparking terminals 2 and 3 are shown as separated by the usual dis charge wed go 4. This wedge consists of a number of lines. or narrow, shallow grooves, preferably burned into the material located between the sparking terminals, thus forming a comparatively high resistance path through the dielectric for the static discharge.

A cover-plate 6 is fastened to the supporting plate 1 by means of screws or other convenient means.

Radiating from the wedge is a number of shallow grooves, 55. These grooves may be located in either the cover-plate or the supporting plate, or, if desired, they may be in both, as indicated in Fig. 2. Although the grooves are shown as symmetrically locatedin the two plates, it is obvious that they may be difierently arranged, if desired. Through these grooves, the air, as it is compressed by the discharge, is free to expand and to find its way to the outer air. The number of these grooves is immaterial, as long as it is sufficient to accomplish the desired purpose. The arrangement of the grooves is also a matter of fancy, and I do not limit myself to that shown in the drawings. I have found that where grooves of this character are employed in connection with the lightning arrester above mentionedthe tend-' ency to rupture of the plates on the occurrence of discharges is reducedto a minimum,

and the length of life of a given device is and an interposed dischargeavedge, one or both of said blocks or plates having a plurality of grooves extending outward laterally from said wedge, substantially as described.

In testimony whereof I have hereunto subscribed my name this 26th day of February, A. D. 1894.

ALEXANDER WURTS. Witnessest JAMES W. SMITH, HUBERT O. TENER. 

